Removed R reference in ROOT project description. (#764)

Author: agheata

_gsdocs-projects/2020/project_ROOT.md

@@ -6,7 +6,7 @@ description: |
   [ROOT](http://root.cern.ch) is a modular scientific software framework developed by [CERN](http://cern.ch) and other Particle Physics laboratories.
   It was originally designed for particle physics data analysis, but it is also used in other applications such as astronomy, bio-informatics, finances, etc.
   It provides all the functionalities needed to deal with big data processing, statistical analysis, data visualisation and data storage.
-  It is mainly written in C++ but integrated with other languages such as Python and R.
+  It is mainly written in C++ but integrated with other languages such as Python.
 summary: |
   A modular scientific software framework. It provides all the functionalities needed to deal with big data processing, 
   statistical analysis, visualisation and storage. It is mainly written in C++ but integrated with other languages such